IMMUNE RESPONSE TO INSULIN IN MAN

胰岛素自身抗体是I型或胰岛素前症状的一部分 依赖性糖尿病（IDDM）和抗人胰岛素抗体 常规伴随糖尿病治疗。 为了了解基因和 胰岛素抗体的结构特征，抗胰岛素B细胞， 分离自治疗的IDDM患者的核苷酸序列， 测定表达的VH和VL基因。 数据显示，大多数反 胰岛素V基因是体细胞突变的，并且一组相关的VH-III基因 优先表达。重要的是，这些抗胰岛素VH基因是 不同于在发育或胎儿谱系中发现的VH-III基因 在系统性疾病中常被自身抗体所使用。 那里 没有关于胰岛素自身抗体的遗传起源或结构的数据 胰岛素依赖型糖尿病 然而，NOD小鼠的研究表明， 胎儿VH基因的表达和调节存在于IDDM中。 因此，本项目将检验克隆扩张的假设， 发育调控的VH基因的体细胞突变起关键作用 在胰岛素依赖型糖尿病中耐受性丧失和胰岛素自身抗体的产生。 具体而言，其目的是表征 通过首先产生IgG抗胰岛素克隆， 以及使用逆转录酶/PCR来鉴定在一个细胞中的VH和VL结构。 IgG抗胰岛素队列。 然后将来自IgG的分子探针 用于鉴定抗胰岛素cDNA文库中的克隆相关元件 以及来自供体的记忆B细胞。 第二个目标是利用这些 技术来测试外源性胰岛素扭曲抗- 胰岛素库表达不同于通过选择的V基因， 胰岛素依赖型糖尿病。 基因因素，克隆主导胰岛素自身免疫， 以及生殖系或体细胞来源的贡献 建立了与疾病相关的特殊性的结构。 这些新 遗传和结构标记可改善胰岛素依赖型糖尿病的诊断和治疗 并将提供一种手段来监测侵袭性胰岛素的作用， 糖尿病前期的治疗。

Autoantibodies to insulin are part of the prodrome of type I or insulin dependent diabetes mellitus (IDDM) and antibodies to human insulin routinely accompany treatment of diabetes. To understand the genetic and structural features of insulin antibodies, anti-insulin B cells were isolated from a treated IDDM patient and the nucleotide sequences of expressed VH and VL genes determined. The data indicate that most anti- insulin V genes are somatically mutated and a set of related VH-III genes is preferentially expressed. Importantly, these anti-insulin VH genes are distinct from VH-III genes found in developmental or fetal repertoires that are frequently used by autoantibodies in systemic diseases. There are no data on the genetic origins or structure of insulin autoantibodies in IDDM. However, studies in the NOD mouse indicate that abnormal expression and regulation of fetal VH genes are present in IDDM. Accordingly, this project will test the hypothesis that clonal expansion and somatic mutation of developmentally regulated VH genes play a key role in loss of tolerance and generation of insulin autoantibodies in IDDM. Specifically, the aims are to characterize the structure and function of anti-insulin B cells in IDDM by first producing IgG anti-insulin clones, and using-reverse transcriptase/PCR to identify VH and VL structures in a cohort of IgG anti-insulins. Molecular probes from the IgGs will then be used to identify clonally related elements in anti-insulin cDNA libraries and in memory B cells from the donor. A second aim is to use these techniques to test the hypothesis that exogenous insulin skews the anti- insulin repertoire to express V genes different from those selected by IDDM. Genetic elements that clonally dominate insulin autoimmunity will be identified and the contribution of germline or somatically derived structures to disease-related specificities established. These new genetic and structural markers may improve diagnosis and therapy of IDDM and will provide a means to monitor the effects of aggressive insulin therapy in pre-diabetics.